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Pipelock is an optional security proxy that scans AI agent traffic flowing through Sure. It protects against secret exfiltration, prompt injection, and tool poisoning.

What Pipelock Does

Pipelock runs as a separate proxy service alongside Sure with two listeners:
ListenerPortDirectionWhat it scans
Forward proxy8888Outbound (Sure to LLM)DLP (secrets in prompts), response injection
MCP reverse proxy8889Inbound (agent to Sure /mcp)Prompt injection, tool poisoning, DLP

Forward proxy (outbound)

When HTTPS_PROXY=http://pipelock:8888 is set, outbound HTTPS requests from Faraday-based clients (like ruby-openai) are routed through Pipelock. It scans request bodies for leaked secrets and response bodies for prompt injection.
Covered: OpenAI API calls via ruby-openai (uses Faraday).Not covered: SimpleFIN, Coinbase, Plaid, or anything using Net::HTTP/HTTParty directly. These bypass HTTPS_PROXY.

MCP reverse proxy (inbound)

External AI assistants that call Sure’s /mcp endpoint should connect through Pipelock on port 8889 instead of directly to port 3000. Pipelock scans:
  • Tool call arguments (DLP, shell obfuscation detection)
  • Tool responses (injection payloads)
  • Session binding (detects tool inventory manipulation)
  • Tool call chains (multi-step attack patterns like recon then exfil)

Docker Compose Setup

The compose.example.ai.yml file includes Pipelock. To use it:
1

Download the compose file and Pipelock config

curl -o compose.ai.yml https://raw.githubusercontent.com/we-promise/sure/main/compose.example.ai.yml
curl -o pipelock.example.yaml https://raw.githubusercontent.com/we-promise/sure/main/pipelock.example.yaml
2

Start the stack

docker compose -f compose.ai.yml up -d
3

Verify Pipelock is healthy

docker compose -f compose.ai.yml ps pipelock
# Should show "healthy"

Connecting external AI agents

External agents should use the MCP reverse proxy port:
http://your-server:8889
The agent must include the MCP_API_TOKEN as a Bearer token in requests. Set this in your .env:
MCP_API_TOKEN=generate-a-random-token
MCP_USER_EMAIL=[email protected]

Running without Pipelock

To use compose.example.ai.yml without Pipelock, remove the pipelock service and its depends_on entries from web and worker, then unset the proxy env vars (HTTPS_PROXY, HTTP_PROXY). Or use the standard compose.example.yml which does not include Pipelock.

Helm (Kubernetes) Setup

Enable Pipelock in your Helm values:
pipelock:
  enabled: true
  image:
    tag: "0.3.2"
  mode: balanced
This creates a separate Deployment, Service, and ConfigMap. The chart auto-injects HTTPS_PROXY/HTTP_PROXY/NO_PROXY into web and worker pods.

Exposing MCP to external agents (Kubernetes)

In Kubernetes, external agents cannot reach the MCP port by default. Enable the Pipelock Ingress:
pipelock:
  enabled: true
  ingress:
    enabled: true
    className: nginx
    hosts:
      - host: pipelock.example.com
        paths:
          - path: /
            pathType: Prefix
    tls:
      - hosts: [pipelock.example.com]
        secretName: pipelock-tls
Or port-forward for testing:
kubectl port-forward svc/sure-pipelock 8889:8889 -n sure

Monitoring

Enable the ServiceMonitor for Prometheus scraping:
pipelock:
  serviceMonitor:
    enabled: true
    interval: 30s
    additionalLabels:
      release: prometheus
Metrics are available at /metrics on the forward proxy port (8888).

Eviction protection

For production, enable the PodDisruptionBudget:
pipelock:
  pdb:
    enabled: true
    maxUnavailable: 1
See the Helm chart README for all configuration options.

Pipelock Configuration File

The pipelock.example.yaml file (Docker Compose) or ConfigMap (Helm) controls scanning behavior. Key sections:
SectionWhat it controls
modestrict (block threats), balanced (warn + block critical), audit (log only)
forward_proxyOutbound HTTPS scanning (tunnel timeouts, idle timeouts)
dlpData loss prevention (scan env vars, built-in patterns)
response_scanningScan LLM responses for prompt injection
mcp_input_scanningScan inbound MCP requests
mcp_tool_scanningValidate tool calls, detect drift
mcp_tool_policyPre-execution rules (shell obfuscation, etc.)
mcp_session_bindingPin tool inventory, detect manipulation
tool_chain_detectionMulti-step attack patterns
websocket_proxyWebSocket frame scanning (disabled by default)
loggingOutput format (json/text), verbosity
For the Helm chart, most sections are configurable via values.yaml. For additional sections not covered by structured values (session profiling, data budgets, kill switch), use the extraConfig escape hatch:
pipelock:
  extraConfig:
    session_profiling:
      enabled: true
      max_sessions: 1000

Modes

ModeBehaviorUse case
strictBlock all detected threatsProduction with sensitive data
balancedWarn on low-severity, block on high-severityDefault; good for most deployments
auditLog everything, block nothingInitial rollout, testing
Start with audit mode to see what Pipelock detects without blocking anything. Review the logs, then switch to balanced or strict.

Limitations

  • Forward proxy only covers Faraday-based HTTP clients. Net::HTTP, HTTParty, and other libraries ignore HTTPS_PROXY.
  • Docker Compose has no egress network policies. The /mcp endpoint on port 3000 is still reachable directly (auth token required). For enforcement, use Kubernetes NetworkPolicies.
  • Pipelock scans text content. Binary payloads (images, file uploads) are passed through by default.

Troubleshooting

Check the config file is mounted correctly:
docker compose -f compose.ai.yml logs pipelock
Common issues:
  • Missing pipelock.example.yaml file
  • YAML syntax errors in config
  • Port conflicts (8888 or 8889 already in use)
If AI chat stops working after enabling Pipelock:
# Check Pipelock logs for blocked requests
docker compose -f compose.ai.yml logs pipelock --tail=50
If requests are being incorrectly blocked, switch to audit mode in the config file and restart:
mode: audit
Verify the MCP upstream is configured correctly:
# Test from inside the Pipelock container
docker compose -f compose.ai.yml exec pipelock /pipelock healthcheck --addr 127.0.0.1:8888
Check that MCP_API_TOKEN and MCP_USER_EMAIL are set in your .env file and that the email matches an existing Sure user.

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